A Baltimore pharmacist who was awaiting sentencing after pleading guilty in a federal drug distribution case has been hit with new charges that he paid someone to murder a witness in the case.

David Robinson, 51, a licensed pharmacist who owned and operated the Frankford Family Pharmacy, admitted last fall that he dispensed the painkiller oxycodone and alprazolam, a sedative used to treat anxiety known by its brand name Xanax, outside the scope of his professional practice and not for a legitimate medical purpose.

Robinson’s plea called for him to receive 51 months in prison, and he was awaiting formal sentencing that had been scheduled for today.

Instead, Robinson was brought into U.S. District Court in Baltimore on new charges of murder for hire, retaliating against a witness and commission of a crime while on release. He has been detained on the new charges, and his attorney could not immediately be reached for comment.

In a phone call late last month with someone he allegedly paid $5,000 up front to carry out the murder, Robinson was told that the hit man wanted additional money, new documents show.

On Thursday, Robinson was told the murder had been carried out and he would need to supply the rest of the hit man’s fee. Robinson asked for proof, and was shown images “mocked up to appear to show” the person dead, authorities wrote in court papers. He was arrested after the meeting concluded.

Supervisory Special Agent Todd C. Edwards, the spokesman for the Drug Enforcement Administration’s Baltimore office, said the case “is a perfect example of how pharmaceutical cases that involve doctors or pharmacists have the potential to be just as violent as a street gang case.”

The initial drug investigation began three years ago. Prosecutors say a source told law enforcement that a pharmacist at Frankford Family Pharmacy was knowingly filling fraudulent prescriptions. Between January and July 2016, the source made controlled purchases from Robinson at the East Baltimore pharmacy, using blank prescriptions provided to the source by DEA, prosecutors said.

Robinson, who lives in the Coldspring neighborhood of North Baltimore, also worked a night shift at a CVS pharmacy in Waldorf, where he wrote prescriptions for oxycodone that he believed were for prominent athletes playing in the NFL, NBA and Major League Baseball, according to his plea agreement in that case.

During the execution of search warrants, law enforcement officers recovered $159,862 in cash from Robinson’s home; $46,927 in a briefcase, blank prescriptions, a prescription pad and a loaded 9mm pistol from Robinson’s car; and $60,486 in cash, an AR-15 rifle with a magazine, several boxes of ammunition for the rifle, and records, invoices and receipts from the pharmacy, the U.S. Attorney’s Office said.

After his arrest, Robinson continued to order pills from his vendors, authorities now say. A source for the DEA said “Robinson continued to sell Promethazine and Clonidine and that six months after the raid Robinson was still ordering pills from his vendors,” court records show.

It was that source who told law enforcement that after his arrest, Robinson mentioned the name of someone he believed had cooperated with police leading to his arrest.

“Jokers got to go,” Robinson allegedly said, documents show.

Robinson provided information from the Maryland Judiciary Case Search website on the person he wanted killed, and they got a picture of the person through a contact at the Motor Vehicle Administration.

The source told investigators that they did not know anybody who could kill the person, but “saw a chance to make some money from Robinson” and claimed they knew someone who could carry out the plot. In late 2017, the source told Robinson the job would require $5,000 up front and $5,000 after it was done, and the person deposited the initial $5,000 into their bank account and used it to pay bills, according to court documents.

Robinson regularly questioned the person about the progress, with the person making excuses and saying they were having trouble locating the target.

On three occasions between December and Feb. 7, the source made controlled purchases of drugs from Robinson at the direction of law enforcement at a TGI Friday’s in West Baltimore, buying hundreds of Chlonidine pills in stock pharmacy bottles each time, law enforcement said.

Chlonidine is a sedative used to treat pain, attention deficit/hyperactivity disorder and high blood pressure.

The source got Robinson talking about the murder-for-hire plot again in January 2019, investigators say, by saying additional money would be needed to use a “subcontractor.”

“I wouldn’t have given him that dough … he already agreed to one price that we agreed to ... now it’s like he got a subcontractor and we paying them both,” Robinson said in a text message.